The experiments in this proposal are directed towards understanding the anatomical and functional organization of three cortical areas in primate visual cortex. There are three sets of experiments in cortical area MT of the Old World monkey. In the first set, we make long microelectrode perforations through area MT, recording single unit activity in response to a range of visual stimuli. The visual stimuli are all designed to reveal differences in receptive fields. Later those differences can be correlated with histological labelling of the area MT "bands" (labelled with deoxyglucose and specific visual stimuli) or the area MT "patches" (labelled with cytochrome oxidase). In the second set, we use a new double-label deoxyglucose protocol to investigate the functional architecture of area MT. One experiment compares the architecture of the bands to the patches. Two other double-labelled deoxyglucose experiments will be done in the awake behaving monkey. These experiments are designed to examine functional organization in higher-tier cortical visual areas. In the third set, we inject various neural tracers into visual areas of the brain, to find which areas (or which columns in which areas) share connections with the MT bands or the MT patches. The final set of experiments is designed to begin studying areas V3 and DM. In one experiment, we plan to record from cells in the area DM "stripes" and "interstripe" regions, to see how those cells respond. In another, we use deoxyglucose and cytochrome oxidase staining techniques to investigate the functional organization of area V3. Finally, we use neural tracers to try to discover the specific connections with the V3 patches and interpatches.